for name [ [ in [ word ... ] ] ; ] do list ; done
       The  list of words following in is expanded, generating a list of items.  The variable name is set
       to each element of this list in turn, and list is executed each time.  If the in word is  omitted,
       the  for  command  executes  list  once  for each positional parameter that is set (see PARAMETERS
       below).  The return status is the exit status of the last command that executes.  If the expansion
       of  the  items  following  in  results  in an empty list, no commands are executed, and the return
       status is 0.

maintain crontab files for individual users (Vixie Cron)

Before a command is executed, its input and output may be redirected using a special notation interpreted
by  the  shell.   Redirection  may  also  be used to open and close files for the current shell execution
environment.  The following redirection operators may precede or appear anywhere within a simple  command
or may follow a command.  Redirections are processed in the order they appear, from left to right.

Redirecting Output
    Redirection of output causes the file whose name results from the expansion of  word  to  be  opened  for
    writing  on  file descriptor n, or the standard output (file descriptor 1) if n is not specified.  If the
    file does not exist it is created; if it does exist it is truncated to zero size.

    The general format for redirecting output is:

           [n]>word

    If the redirection operator is >, and the noclobber option to the  set  builtin  has  been  enabled,  the
    redirection  will  fail if the file whose name results from the expansion of word exists and is a regular
    file.  If the redirection operator is >|, or the redirection operator is > and the  noclobber  option  to
    the  set  builtin  command  is  not  enabled, the redirection is attempted even if the file named by word
    exists.